MYTH: Stainless steel doesn’t rust. Adhesives and seawater can contain chlorides which penetrate the rust protective layer found on stainless steel. So make sure you peel off that old tape at the end of the sailing season and start fresh next year.

That ring pin is about to shear!!

This is a perfect example of wasting your time and doing it wrong. These custom made link plates should be replaced with a standard, readily available, eye-jaw-toggle.

2 thoughts on “Views from Aloft”

According to eq 1, rusting is the product of oxidation. If stainless or any other iron alloy is deprived of oxygen, it cannot rust. The rust that appears under or around the tape on stainless is probably the product of exposure rather than deprivation. The thin layer of metal oxide that forms on the surface of stainless when in contact with oxygen is most likely damaged by the tape or the aggregation of salts at the edges of the tape. Thus, oxygen can seep through or under the tape and make contact with the iron in the stainless, causing rust to form. Furthermore, the aggregation of salts at the edges of the tape will enhance the rate of oxidation (i.e. rusting) through electrochemical means. By removing the tape, cleaning the stainless, and subsequently allowing the entire surface to oxidize, the thin layer of metal oxide is replenished, passivating the formation of rust by depriving the bulk of the alloy of oxygen.

Thanks for this. Although my job is to work with certain metals regularly (aircraft grade aluminum, bronze, and 316 grade stainless steel), I am no metallurgist. I love comments like this, because there is always something to learn in this world. So, thank you. It seems that after some research that, just as you said, it is the reaction of the O2 and the Chromium that forms a ceramic layer (chromium oxide) which protect the metals beneath the surface, thus keeping the alloy beneath it from rusting. After some reading it appears there are many reasons this protective layer to be penetrated. The main one, T least for our industry, seems to be chlorides. Which apparently are found in seawater and also adhesives (amongst others as well). Now that you have brought this to my attention it will be noted that this surface rusting we are seeing on this rigging toggle is perhaps due to the chromium oxide layer being disrupted by contaminants, likely chlorine, trapped on the surface by the tape, or even the adhesive itself?

Either way, I like that we can both agree that keeping your stainless steel clean and free of contaminants is the best way to ensure stainless steel stays rust free.

Again thanks for the thoughtful comment…AND for taking a look at the view.